Electronics question

[Tooeez]

It's time to upgrade my fishfinder/gps, and I am not sure of which way to go. Now I have a 10" Lowrance combo unit on the bridge, and a 5" Lowrance fishfinder in the cockpit, with an a/b switch to switch the transducer input between them. For the new setup I want to get side imaging and down imaging capability for the bridge unit, and the ability for the 2 units to network together to share one transducer so I can monitor the cockpit unit while drift fishing. I am comparing the Lowrance Elite Ti2 and HDS Live units, the Garmin GPSMap XSV units, and the Hummingbird Helix units, and they all seem to be similar in price and capability. Does anyone have any experience or thoughts on any of these units, or any other input on the best way to set up this kind of electronics package?